[folivier]

Another option is the Ready Brake system which utilizes a surge brake built into the towbar or a standalone surge brake that slides into your coach receiver then your towbar slides into the surge brake. Then you have a cable that attaches to your toad that is attached to your toad's brake pedal. Easy to hook/unhook and is proportional since whenever your toad is going faster than your coach it activates the toad's brakes to slow it down to match the coach speed.
I've been using this for about 10 years now and pleased with it.
https://www.readybrake.com